#include <iostream>

bool isPrime(int num) {
    if (num <= 1) return false;
    for (int i = 2; i * i <= num; ++i) {
        if (num % i == 0) return false;
    }
    return true;
}

int main() {
    int number;
    std::cin >> number;
    if (number <= 2 || number > 10000 || number % 2 != 0) {
        std::cout << "invalid input" << std::endl;
    } else {
        int count = 1;
        for (int i = 2; i <= number / 2; ++i) {
            if (isPrime(i) && isPrime(number - i)) {
                std::cout << count << ": " << i << " " << number - i << std::endl;
            }
        }
    }
    return 0;
}